Xanax (alprazolam) is a benzodiazepine medication used to treat anxiety and panic disorders. It works by slowing down the central nervous system, which produces a calming effect. Xanax is a prescription medication, meaning it can only be obtained legally with a doctor's prescription. However, there are some online pharmacies that sell Xanax without a prescription. This can be a dangerous practice, as it can lead to serious health problems if the medication is not taken as directed.